HP MSR Router Series User Manual

97
Ste
p
Command Remarks
2. Enter synchronous-mode serial
interface view or POS
interface view.
interface interface-type
interface-number
N/A
3. Enable HDLC encapsulation
on the interface.
link-protocol hdlc
PPP encapsulation is enabled by
default.
Configuring link status polling
An HDLC-enabled interface can regularly check link status by sending keepalives to the peer at the
keepalive interval at the link layer. A keepalive carries the local sender sequence number and the last
received sequence number of the peer.
After sending a keepalive, an interface increments the sender sequence number by 1 in the next
keepalive when the following conditions exist:
• The interface receives a response within the keepalive interval.
• The response carries the sender sequence number in the sent keepalive.
After sending a keepalive, if the interface does not receive a response within the keepalive interval, it
resends the keepalive with an unchanged sequence number. When the keepalive retry limit is reached,
the interface considers the link faulty and reports a link layer down event.
When you configure link status polling, follows these restrictions and guidelines:
• Link status check is disabled if you set the keepalive interval to 0.
• HP recommends that you set the same keepalive interval for the two ends of a link.
• If the network has a long delay or is experiencing congestion, you can increase the keepalive
interval to prevent the link from being closed.
To configure link status polling:
Ste
p
Command Remarks
1. Enter system view.
system-view
N/A
2. Enter interface view.
interface interface-type
interface-number
N/A
3. Set the keepalive
interval.
timer hold seconds By default, the keepalive interval is 10 seconds.
4. Set the keepalive retry
limit.
timer-hold retry retry By default, the keepalive retry limit is 5.
Displaying and maintaining HDLC
Execute display commands in any view and reset commands in user view.
Task Command
Display the HDLC configuration
on an interface.
display interface serial interface-number
display interface pos interface-number

HP MSR Router Series Specifications

General

Brand	HP
Model	MSR Router Series
Category	Network Router
Language	English